// URL: https://yukicoder.me/problems/no/665

import std.algorithm, std.array, std.bitmanip, std.container, std.conv, std.format,
       std.functional, std.math, std.range, std.traits, std.typecons, std.stdio, std.string;

version(unittest) {} else
void main()
{
  long n; int k; io.getV(n, k);

  auto fact = Fact!mint(k+2);

  auto b = new mint[](k+1);
  b[0] = 1;
  foreach (i; 1..k+1) {
    if (i >= 3 && i%2 == 1) continue;
    foreach (j; 0..i)
      if (i == 1 || i%2 == 0)
        b[i] -= fact.combi(i+1, j)*b[j];
    b[i] *= mint(i+1).inv;
  }

  auto s = mint(0), nb = mint(n+1);
  foreach_reverse (i; 0..k+1) {
    if (i == 1 || i%2 == 0)
      s += fact.combi(k+1, i)*b[i]*nb;
    nb *= mint(n+1);
  }
  s *= mint(k+1).inv;

  io.put(s);
}

struct Fact(T, bool inv = true)
{
  int n;
  T[] table;
  alias table this;
  static if (inv) T[] invTable;

  pure nothrow @safe
  {
    this(int n)
    {
      this.n = n;

      table = new T[](n+1); table[0] = 1;
      foreach (i; 1..n+1) table[i] = table[i-1]*i;

      static if (inv) {
        invTable = new T[](n+1); invTable[n] = T(1)/table[n];
        foreach_reverse (i; 1..n+1) invTable[i-1] = invTable[i]*i;
      }
    }
  }

  pure nothrow @nogc @safe
  {
    static if (inv) {
      T perm(size_t a, size_t b)
        in { assert(n >= a && a >= b); }
      do
      {
        return table[a]*invTable[a-b];
      }

      T combi(size_t a, size_t b)
        in { assert(n >= a && a >= b); }
      do
      {
        return table[a]*invTable[b]*invTable[a-b];
      }

      T homo(size_t a, size_t b)
        in { assert(n >= a+b-1); }
      do
      {
        return combi(a+b-1, b);
      }
    }
  }
}

const mod = 10^^9+7;
alias mint = ModInt!mod;
pure nothrow @nogc @safe
{
  auto lowerBoundBy(alias conv = "a", alias comp = "a<b", R, T)(R a, T v)
  {
    return a.sortedTuple!(conv, comp).lowerBound(tuple(a.front, v)).map!"a[0]";
  }

  auto upperBoundBy(alias conv = "a", alias comp = "a<b", R, T)(R a, T v)
  {
    return a.sortedTuple!(conv, comp).upperBound(tuple(a.front, v)).map!"a[0]";
  }

  auto sortedTuple(alias conv = "a", alias comp = "a<b", R)(R a)
  {
    alias convFun = unaryFun!conv, compFun = binaryFun!comp;
    return a.map!(e => tuple(e, convFun(e))).assumeSorted!((a, b) => compFun(a[1], b[1]));
  }
}

pure nothrow @nogc @safe
{
  T isqrt(T)(T n)
    if (is(T == int) || is(T == long))
  {
    static if (is(T == int)) auto max = 46_341;
    else static if (is(T == long)) auto max = 3_037_000_500L;
    return iota(T(0), max).lowerBoundBy!("a^^2", "a<=b")(n).back;
  }

  T icbrt(T)(T n)
    if (is(T == int) || is(T == long))
  {
    static if (is(T == int)) auto max = 1_291;
    else static if (is(T == long)) auto max = 2_097_152L;
    return iota(T(0), max).lowerBoundBy!("a^^3", "a<=b")(n).back;
  }

  ExtGcdResult!T extGcd(T)(T a, T b)
  {
    if (a == 0) {
      return ExtGcdResult!T(b, T(0), T(1));
    } else {
      auto r = extGcd(b%a, a);
      return ExtGcdResult!T(r.gcd, r.y-(b/a)*r.x, r.x);
    }
  }

  struct ExtGcdResult(T)
  {
    T gcd, x, y;
  }
}

pure nothrow @safe
{
  T powr(alias pred = "a*b", T, U)(T a, U n, T one)
  {
    alias predFun = binaryFun!pred;
    if (n == 0) return one;
    auto r = one;
    for (; n > 0; n >>= 1) { if (n&1) r = predFun(r, a); a = predFun(a, a); }
    return r;
  }
  T powr(alias pred = "a*b", T, U)(T a, U n)
  {
    return powr!(pred, T, U)(a, n, T(1));
  }
}

struct ModInt(int m, bool pos = false)
{
  pure nothrow @nogc @safe:
  @property int value() { return i; }
  @property void value(int v) { i = nm(v); }
  alias value this;

  this(T)(T v)
    if (isIntegral!T)
  {
    i = nm(v);
  }
  ref Mint opAssign(T)(T v)
    if (isIntegral!T)
  {
    i = nm(v);
    return this;
  }
  ref Mint opAssign(Mint v)
  {
    i = v.i;
    return this;
  }

  static if (!pos) {
    Mint opUnary(string op: "-")() const
    {
      return Mint(-i);
    }
  }

  static if (m < int.max / 2) {
    Mint opBinary(string op, T)(T r) const
      if ((op == "+" || (!pos && op == "-")) && isIntegral!T)
    {
      return Mint(mixin("i"~op~"r"));
    }
    ref Mint opOpAssign(string op, T)(T r)
      if ((op == "+" || (!pos && op == "-")) && isIntegral!T)
    {
      i = nm(mixin("i"~op~"r"));
      return this;
    }
  } else {
    Mint opBinary(string op, T)(T r) const
      if ((op == "+" || (!pos && op == "-")) && isIntegral!T)
    {
      return Mint(mixin("l"~op~"r"));
    }
    ref Mint opOpAssign(string op, T)(T r)
      if ((op == "+" || (!pos && op == "-")) && isIntegral!T)
    {
      i = nm(mixin("l"~op~"r"));
      return this;
    }
  }
  Mint opBinary(string op: "*", T)(T r) const
    if (isIntegral!T)
  {
    return Mint(l*r);
  }
  ref Mint opOpAssign(string op: "*", T)(T r)
    if (isIntegral!T)
  {
    i = nm(l*r);
    return this;
  }

  Mint opBinary(string op)(Mint r) const
    if (op == "+" || !pos && op == "-" || op == "*")
  {
    return opBinary!op(r.i);
  }
  ref Mint opOpAssign(string op)(Mint r)
    if (op == "+"|| !pos && op == "-" || op == "*")
  {
    return opOpAssign!op(r.i);
  }

  Mint opBinary(string op: "^^", T)(T n)
    if (isIntegral!T)
  {
    return powr(this, n, Mint(1));
  }

  static if (!pos) {
    Mint opBinary(string op: "/")(Mint r)
    {
      return Mint(l*r.inv.i);
    }
    ref Mint opOpAssign(string op: "/")(Mint r)
    {
      i = nm(l*r.inv.i);
      return this;
    }

    Mint opBinary(string op: "/", T)(T r)
      if (isIntegral!T)
    {
      return opBinary!op(Mint(r));
    }
    Mint opOpAssign(string op: "/", T)(T r)
      if (isIntegral!T)
    {
      return opOpAssign!op(Mint(r));
    }

    Mint inv()
    {
      return Mint(extGcd(i, m).x);
    }
  }

  private
  {
    alias Mint = ModInt!(m, pos);
    version(BigEndian) union { long l; struct { int i2; int i; } }
    else union { long l; int i; }

    pure nothrow @nogc @safe
    {
      int nm(T)(T v) const
        if (isIntegral!T)
      {
        static if (pos) return cast(int)(v%m);
        else return cast(int)((v%m+m)%m);
      }
    }
  }
}

auto io = IO!()();
import std.stdio;
struct IO(alias IN = stdin, alias OUT = stdout)
{
  import std.meta : allSatisfy;
  import core.stdc.stdlib : exit;

  void getV(T...)(ref T v)
  {
    foreach (ref w; v) get(w);
  }
  void getA(T)(size_t n, ref T v)
    if (hasAssignableElements!T)
  {
    v = new T(n);
    foreach (ref w; v) get(w);
  }
  void getC(T...)(size_t n, ref T v)
    if (allSatisfy!(hasAssignableElements, T))
  {
    foreach (ref w; v) w = new typeof(w)(n);
    foreach (i; 0..n) foreach (ref w; v) get(w[i]);
  }
  void getM(T)(size_t r, size_t c, ref T v)
    if (hasAssignableElements!T && hasAssignableElements!(ElementType!T))
  {
    v = new T(r);
    foreach (ref w; v) getA(c, w);
  }
  template getS(E...)
  {
    void getS(T)(size_t n, ref T v)
    {
      v = new T(n);
      foreach (ref w; v) foreach (e; E) mixin("get(w."~e~");");
    }
  }

  const struct PutConf
  {
    bool newline = true, flush, exit;
    string floatFormat = "%.10f", delimiter = " ";
  }

  void put(alias conf = "{}", T...)(T v)
  {
    mixin("const PutConf c = "~conf~"; putMain!c(v);");
  }
  void putB(alias conf = "{}", S, T)(bool c, S t, T f)
  {
    if (c) put!conf(t);
    else put!conf(f);
  }
  void putRaw(T...)(T v)
  {
    OUT.write(v);
    OUT.writeln;
  }

  private
  {
    dchar[] buf;
    auto sp = (new dchar[](0)).splitter;

    void nextLine()
    {
      IN.readln(buf);
      sp = buf.splitter;
    }
    void get(T)(ref T v)
    {
      if (sp.empty) nextLine();
      v = sp.front.to!T;
      sp.popFront();
    }

    void putMain(PutConf c, T...)(T v)
    {
      foreach (i, w; v) {
        putOne!c(w);
        if (i+1 < v.length) OUT.write(c.delimiter);
      }
      static if (c.newline) OUT.writeln;
      static if (c.flush) OUT.flush();
      static if (c.exit) exit(0);
    }
    void putOne(PutConf c, T)(T v)
    {
      static if (isInputRange!T && !isSomeString!T) putRange!c(v);
      else static if (isFloatingPoint!T) OUT.write(format(c.floatFormat, v));
      else static if (hasMember!(T, "fprint")) v.fprint(OUT);
      else OUT.write(v);
    }
    void putRange(PutConf c, T)(T v)
    {
      auto w = v;
      while (!w.empty) {
        putOne!c(w.front); w.popFront();
        if (!w.empty) OUT.write(c.delimiter);
      }
    }
  }
}